Divine Bolts ddi is an implement power, so rules as written, you can't.

You might however be able to either get your DM to approve the combination, or to get your DM to approve the combination when using an implement that is also a weapon (and thus requiring the investment of another feat).

In allowing the combo, I would rule that Rapid Shot's override of a normal RBA's targeting rules also overrides Divine Bolt's targeting. Meaning that you are not getting creating two area burst 1 attacks.

Overall, I don't see any real balance issues with doing this - it's a multi feat, paragon tier trick for an at will, ranged basic, area burst 1, Wis-2 vs Reflex, 1d6+Wisdom attack.

Lots of feats for a slightly improved Blazing Starfall.

Were I DMing, I would be happy to allow this combination for Divine Bolts, but probably would disallow it for Magic Missile, as the latter is unable to take a penalty to the attack roll.

Note: I call the rapid shotted bolts area burst 1, because in almost all cases that is how they behave, but unless Rapid Shot gets errata to change from being a ranged attack that targets things in a bunch of squares, these are not area bursts and so for monsters like swarms and their area burst vulnerabilities, are not as deadly.

Er, divine bolts is "attack 2 targets" instead of Area Burst 1. So quite a lot of cheese can be had from it. So, in the "optimal" case,I'd attack 9 targets in the area burst 1 (hahaha) and then have 9 shots to do with as I wanted.
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Brian Ballsun-Stanton♦Jan 25 '11 at 23:37